Biopsy needle

ABSTRACT

A COMPOSITE DISPOSABLE BIOPSY NEEDLE COMPRISING AN INNER NEEDLE DISPOSED WITHIN AN OUTER NEEDLE AND FIXEDLY SECURED THERETO. THE DISTAL ENDS OF THE NEEDLE AND FIXEDLY VIDED WITH COEXTENSIVE SETS OF PRONGS TERMINATING IN TISSUE PIERCING APEXES. THE DISTAL END OF THE INNER NEEDLE IS JOINED TO THE BODY PORTION THEREOF BY A WEAKENED WALL PORTION ADAPTED TO COLLAPSE UPON RELATIVE ROTATIONAL MOVEMENT BETWEEN THE INNER AND OUTER NEEDLES TO SEVER AND CAPTURE A BIOPSY SPECIMEN IN THE INNER NEEDLE.

Sept. 20, 1971 l. HA LLAC BIOPSY NEEDLE Filed Nov. 5, 1969 INVENTOR ATTORNEYS,

United States Patent ()fice Patented Sept. 20, 1971 3,605,721 BIOPSY NEEDLE Ismet Hallac, 94 Sudbury Lane, Williamsville, N.Y. 14221 Filed Nov. 3, 1969, Ser. No. 873,343 Int. Cl. A61b /10 US. Cl. 1282B Claims ABSTRACT OF THE DISCLOSURE A composite disposable biopsy needle comprising an inner needle disposed Within an outer needle and fixedly secured thereto. The distal ends of the needles are provided with coextensive sets of prongs terminating in tissue piercing apexes. The distal end of the inner needle is joined to the body portion thereof by a weakened wall portion adapted to collapse upon relative rotational movement between the inner and outer needles to sever and capture a biopsy specimen in the inner needle.

BACKGROUND OF THE INVENTION This invention relates to a biopsy needle and, more particularly, to a disposable composite biopsy needle for extracting biopsy specimens from human tissue.

Many medical instruments have been devised in recent years to obtain biopsy specimens of living body tissue without the necessity of performing conventional surgery from the exterior of the body. Such instruments often employ sharp-edged blades for severing the tissue together with sheathing members which move axially relative to the blades for encapsulating the biopsy specimen. Sometimes the blades are moved apart into the tissue prior to the severing operation so that a greater lateral area of human tissue is penerated than is necessary. Also, many such instruments penetrate beyond the area in which the specimen is to be obtained so that adjacent areas are penetrated. In some of these instruments, and particularly in those wherein the severing blades or prongs are initially spread apart, a primary blood vessel may be inadvertently captured and severed, resulting in excessive and detrimental loss of blood to patients. After such an occurrence, medical personnel are reluctant to take biopsies for a while so that there is a tendency to perform surgery or other medical work without benefit of biopsies.

Other prior known biopsy instruments employ a number of somewhat complex, movablecomponents which require considerable time to assemble and use. After use, these components must be disassembled, individually cleaned, sterilized, and reassembled for further use.

SUMMARY OF THE INVENTION An object of the present invention is to provide an im proved disposable biopsy needle which is simple and inexpensive in construction, safe to use, expedient and reliable in operation, and which can be discarded after use.

Another object of this invention is to provide the foregoing biopsy needle with improved means to capture a specimen substantially at the depth of penetration without affecting other adjacent areas.

The disposable biopsy needle of the present invention is characterized by the provision of inner and outer needle members joined together at their distal ends to form a composite biopsy needle. The distal ends of the needle members are provided with coextensive sets of prongs terminating in apexes for facilitating the piercing and penetration of human tissue. The distal end of the inner needle member is joined tothe body portion thereof by a weakened wall portion comprising a plurality of narrow bars circumferentially spaced by slits or openings cut into the weakened wall portion. The weakened wall portion is adapted to collapse upon relative rotational movement between the inner and outer needle members to sever and capture a biopsy specimen therein.

The foregoing and other objects, advantages and characterizing features of the present invention will become clearly apparent from the ensuing detailed description of certain illustrative embodiments thereof, taken together with the accompanying drawings wherein like reference numerals denote like parts throughout the various views.

BRIEF DESCRIPTION OF THE DRAWING FIGURES FIG. 1 is a side elevational view of a composite biopsy needle of this invention showing a trochar fitted therein;

FIG. 2 is an end elevational view of the composite biopsy needle of FIG. 1, taken about on line 22 of FIG. 1;

FIG. 3 is a fragmentary side elevational view of the outer needle of the composite biopsy needle of FIG. 1;

FIG. 4 is a fragmentary side elevational view of the inner needle of the composite biopsy needle of FIG. 1;

FIG. 5 is a fragmentary longitudinal sectional view, on an enlarged scale, of the composite needle shown in FIG. 1 illustrating the weakened wall portion of the inner needle;

FIG. 6 is a view similar to FIG. 5 but illustrating the weakened wall portion in a collapsed condition;

FIG. 7 is a view similar to FIG. 6 showing the weakened wall portion severed; and

FIG. 8 is a fragmentary side elevational view of a modified form of the inner needle of this invention.

DESCRIPTION OF AN ILLUSTRATIVE EMBODIMENT Referring now in detail to the drawing, there is shown in FIG. 1 an illustrative embodiment of a composite, disposable, biopsy needle constructed in accordance with the present invention and generally designated 10', comprising an outer tubular member or needle 12 having a suitable handle 18 at one end thereof. Inner needle 16 is adapted to be received within outer needle 12 and is generally coaxial therewith. Needles 12 and. 16 are preferably formed of a thin-walled, surgical, stainless steel tubing. While dimensions may vary to suit various conditions and purposes, the outside diameter of outer needle 12 is on the order of 1.2 mm. in one example. Handles 14 and 18 can be formed of any suitable material bonded or otherwise fixedly secured to the outer cylindrical surfaces of needles 12 and 16, respectively.

The reference character 20 designates a fitted stylet or trochar assembled inside the inner needle 16 it is inserted into the tissue. Trochar 20 is formed of solid stock and is of a diameter to snugly fit in inner needle 16'. Trochar 20 is provided at its distal end with a point 22 adapted to project beyond the ends of inner and outer needles 16 and 12. The other end of trochar 20 is provided with a handle 14 having a hub 26 which fits within a cavity of handle 18.

When the fitted trochar 20 is inserted in inner needle 16, hub 26 is snugly received in cavity 28 with the solid body portion of trochar 20 reinforcing the walls of the composite biopsy needle 10. Suitable means are provided in order to prevent relative rotation between trochar 20 and the inner needle 16, such means comprising a lug 30 fixed to the inner side of handle 24 and projecting into a notch 32 in a flange 34 of handle 18. In a similar construction, a lug 36 can be provided on the inner side of handle 18 for insertion into a notch 38 provided in a flange 40 of handle 14 to prevent accidental or inadvertent relative rotation between inner and outer needles 16 and 12, respectively, prior to or during tissue penetration.

Outer needle 12 (FIG. 3) is cylindrical in shape and is provided with a body portion having equally spaced knifeedged projections or prongs 42 extending axially outwardly of needle 12 at the distal end thereof remote from handle 14. Prongs 42 are of generally V-shaped configuration and terminate in apexes 44 adapted to pierce and penetrate human body tissue. Although four equally spaced prongs are illustrated, it should be understood that any desired number arranged in any suitable pattern may be employed, as desired. Moreover, apexes 44 can lie in a. common transaxial plane normal to the axis of needle 12 as illustrated in FIG. 3 or in a transaxial plane inclined to the axis of needle 12.

Inner needle 16 is cylindrical in shape and has a body portion of a slightly lesser diameter than outer needle 12 so as to be telescopically received therein. The distal end of needle 16 also is provided with prongs 46 equal in number and substantially similar in configuration to prongs 42 of needle 12, terminating in apexes 48.

Inner needle 16 is weakened adjacent the distal end thereof by removing portions therefrom to form four elongated, relatively, narrow connecting bars 50 between the distal end of needle 16 and the body portion thereof (FIG. Bars 50 define generally rectangular slits or openings 52 therebetween and these may be formed by drilling or any other suitable metal removing operation. Of course, any necessary or desired number of bars 50 can be provided within the purview of this invention.

An alternate construction is illustrated in FIG. 8 wherein the weakened portion can be formed by grinding through inner needle 16 at right angles to form generally elliptical openings 54 defining bars 56 which are arcuately curved along opposite sides to form reduced width portions 58 at the midpoints of bars 56 and progressively wider portions 60 extending in opposite directions and which merge into said distal end and said body portion, respectively. The grinding operation leaves razor sharp cutting edges along the marginal edges of bars 56 to facilitate the tissue severing operation hereinafter described. Still another expedient would be to form circular openings in needle 16 by cross drilling therethrough at right angles to form a weakened wall portion.

In assemblying the biopsy needle of the present invention, inner needle 16 is snugly fitted into outer needle 12 with prongs 46 coinciding with prongs 42 whereby the walls of the exposed edges are tapered in a common plane. The distal ends of needles 12 and 16 can be fastened together by a suitable solder admitted through an opening 62 provided in outer needle 12 (FIG. 5 or otherwise fixedly secured together as shown at 64 in FIGS. 5 and 6.

The composite biopsy needle can be enclosed in a protective plastic bag or container, with or without a trochar 20, in a sterilized condition ready for use when needed.

In use, with trochar 20 fitted into the composite biopsy needle and with point 22 projecting outwardly thereof, the initial perforation is made through the skin of the patient into the tissue until the leading or distal end is inserted to the point where it is desired to obtain the tissue specimen. Trochar is then removed from biopsy needle 10, which is further penetrated into the tissue until such tissue is disposed in the distal end of inner needle 16 inwardly of bars 50. Handles 14 and 18 are then axially moved apart slightly to remove lug 36 from notch 38 and manipulated to rotate needles 12 and 16 relative to each other, thereby twisting bars as shown in FIG. 6 to deform or collapse the weakened wall portion of inner needle 16. Needles 12 and 16 are further twisted until bars 50 are severed as shown in FIG. 7 to sever and trap a specimen of the tissue within inner needle 1-6. The distal end of inner needle 16 projects forwardly of the trapped specimen a distance of approximately 2 mm. so that biopsy needle 10 is penetrated substantially to the depth at which the biopsy specimen is obtained. In this manner, the depth of penetration is restricted to the area where the biopsy specimen is obtained. Also, the area penetrated is localized within the confines of outer needle 12. The composite biopsy needle 10 is then removed from the patient with the biopsy specimen captured in a cleancut circular core form within inner needle 16. The biopsy specimen is then removed for analysis and the composite biopsy needle discarded.

From the foregoing, it is seen that the present invention fully accomplishes its intended objects and provides an improved disposable biopsy needle which can be discarded after use thereby eliminating excessive handling occasioned by cleaning, sterilizing, and reassembling. By the provision of a weakened wall portion adjacent the distal end of the needle, a biopsy specimen can be captured substantially to the depth of penetration of the needle as opposed to many conventional needles which require penetration well beyond the area from which the specimen is obtained. Also, penetration is localized in an axial zone without irritating or affecting laterally adjacent areas or extending substantially beyond the desired area from which the biopsy specimen is to be obtained. Moreover, the specimen obtained is in the form of an undamaged cylindrical core which can be easily analyzed.

Preferred forms of this invention having been disclosed in detail, it is to be understood that this has been done by way of illustration only.

I claim:

1. A disposable biopsy needle comprising a hollow outer needle and a hollow inner needle telescopically received within said outer needle, said outer needle having a body portion and a distal end provided with prongs terminating in apexes, said inner needle having a body portion, a distal end and deformable means adjacent said distal end collapsing upon relative rotational movement between said inner and outer needles to capture a biopsy specimen within said inner needle.

2. A disposable biopsy needle according to claim 1 wherein said means comprises a weakened wall portion.

3. A disposable biopsy needle according to claim 1 wherein said distal end of said inner needle is fixed to said outer needle.

4. A disposable biopsy needle according to claim 1 wherein said distal end of said inner needle is provided with prongs terminating in apexes substantially coinciding with said prongs and apexes of said outer needle.

5. A disposable biopsy needle according to claim 1 wherein said means comprises a plurality of bars interposed between said body portion and said distal end of said inner needle.

6. A disposable biopsy needle according to claim 1 wherein said inner and outer needles are provided with handles, respectively, for facilitating rotational movement between said needles.

7. A disposable biopsy needle according to claim 1 wherein said inner and outer needles are formed of thinwalled steel tubing.

8. A disposable biopsy needle according to claim 5 wherein said bars comprise narrow, thin strips connecting said distal end to said body portion.

9. A disposable biopsy needle according to claim 5 wherein said bars have narrow central portions and progressively wider arcutate portions extending in oppo- References Cited UNITED STATES PATENTS 6/1956 Ullery 1282B 9/ 1961 Silverrnan 1282B 6 Naz 128-2B Hustad 128-263 Royce 1282B(UX) Stewart 1282B Dwyer et al. 1282B Bulloch 1282B Robinson 128-2B ALDRICH F. MEDBERY, Primary Examiner 

